U.S. patent number 5,833,650 [Application Number 08/464,579] was granted by the patent office on 1998-11-10 for catheter apparatus and method for treating occluded vessels.
This patent grant is currently assigned to Percusurge, Inc.. Invention is credited to Mir A. Imran.
United States Patent |
5,833,650 |
Imran |
November 10, 1998 |
Catheter apparatus and method for treating occluded vessels
Abstract
A catheter assembly for treatment of a stenosis in a lumen in a
blood-carrying vessel comprising a first flexible elongate tubular
member having proximal and distal extremities. A first inflatable
balloon is coaxially mounted on the distal extremity of the first
flexible elongate tubular member and has a main lumen and an
aspiration lumen exiting through the distal extremity. A second
flexible elongate tubular member has proximal and distal
extremities and has a second inflatable balloon coaxially mounted
on the distal extremity and has a blood perfusion lumen extending
therethrough. The second flexible elongate tubular member is
slidably mounted in the main lumen of the first flexible elongate
tubular member. The first balloon is positioned so that it is
adjacent to but proximal of the stenosis and is thereafter inflated
to create a first occlusion in the lumen in the vessel. A negative
pressure is created in the lumen in the vessel distal of the first
balloon through the aspiration lumen. The second balloon is
positioned distal of the stenosis and is inflated to create a
second occlusion in the lumen of the vessel to form a working space
between the first and second balloons which brackets the stenosis.
Blood is perfused through the blood perfusion lumen distal of the
second occlusion. A therapeutic procedure is performed in the
working space.
Inventors: |
Imran; Mir A. (Palo Alto,
CA) |
Assignee: |
Percusurge, Inc. (Sunnyvale,
CA)
|
Family
ID: |
23844474 |
Appl.
No.: |
08/464,579 |
Filed: |
June 5, 1995 |
Current U.S.
Class: |
604/509;
604/96.01; 604/508 |
Current CPC
Class: |
A61M
25/1011 (20130101); A61M 2025/1045 (20130101); A61B
2017/320716 (20130101) |
Current International
Class: |
A61M
25/10 (20060101); A61M 029/00 () |
Field of
Search: |
;604/101,96,53
;606/194-196,49 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Coggins; Wynnwood
Assistant Examiner: Gring; N. Kent
Attorney, Agent or Firm: Knobbe, Martens, Olson & Bear,
L.L.P.
Claims
What is claimed is:
1. A method for treating occluded vessels comprising:
first advancing a first catheter having a first inflatable balloon
mounted thereon into a blood vessel until the first balloon is
positioned proximal to a stenosis in the blood vessel;
inflating the first balloon to occlude the blood vessel; and
then
advancing a second catheter across said stenosis until the second
catheter is positioned distal to said stenosis.
2. The method of claim 1, wherein said blood vessel is a saphenous
vein graft.
3. The method of claim 1, wherein said blood vessel is a carotid
artery.
4. The method of claim 1, wherein said second catheter has an
inflatable balloon mounted thereon, and wherein the method further
comprises inflating the balloon on the second catheter after said
second catheter is positioned distal to said stenosis.
5. A method for treating occluded vessel comprising:
first inhibiting a flow of blood across a stenosis in a blood
vessel in a proximal to distal direction; and then
advancing a catheter across said stenosis in a proximal to distal
direction.
6. The method of claim 5, wherein said vessel is substantially
occluded at a site proximal to said stenosis to inhibit said flow
of blood.
7. The method of claim 6, wherein said substantial occlusion is
provided by inflating an inflatable balloon within said blood
vessel at a site proximal to said stenosis.
8. The method of claim 5, wherein the blood flow is inhibited prior
to advancing the catheter across the stenosis.
9. The method of claim 5, wherein the blood flow is inhibited while
the catheter is advanced across the stenosis.
10. The method of claim 5, wherein said catheter is a
guidewire.
11. The method of claim 5, wherein said catheter is a hollow
guidewire bearing an occlusive device.
12. The method of claim 5, wherein the blood flow is inhibited
across the stenosis by negative pressure near said stenosis.
13. A method for treating a stenosis in a bifurcated blood vessel
comprising:
first advancing a first catheter having a first occlusive device
mounted thereon into said blood vessel until the first occlusive
device is positioned proximal to the stenosis;
activating the first occlusive device to occlude the blood
vessel;
advancing a second catheter having a second occlusive device
mounted thereon across said stenosis until the second occlusive
device is positioned distal to said stenosis and in a first branch
of the vessel;
activating the second occlusive device on the second catheter;
advancing a third catheter having a third occlusive device mounted
thereon until the third occlusive device is positioned in a second
branch of the vessel; and
activating the third occlusive device on the third catheter.
14. The method of claim 13, wherein said bifurcated blood vessel is
a carotid artery.
15. The method of claim 13, wherein said occlusive devices are
inflatable balloons and wherein the activating of the occlusive
devices comprises inflating the balloons.
16. The method of claim 5, wherein said blood vessel is a carotid
artery.
17. The method of claim 5, wherein said inhibiting the flow of
blood is achieved by delivering a first catheter having an
occlusive device mounted thereon into the blood vessel and
activating the occlusive device.
18. The method of claim 17, further comprising advancing a second
catheter having a second occlusive device mounted thereon across
said stenosis in a proximal to distal direction after delivery and
activation of the first occlusive device.
19. The method of claim 18, further comprising activating the
second occlusive device after the second catheter is advanced
across the stenosis.
20. The method of claim 19, wherein the first and second occlusive
devices are inflated balloons, and the activation comprises
inflating the balloons .
Description
This invention relates to an apparatus and method for treating
occluded vessels in living bodies and more particularly for
treating occlusions in carotid arteries.
Attempts heretofore have been made to treat occlusions in the
carotid arteries leading to the brain. However, such arteries have
been very difficult to treat because of the possibility of
dislodging plaque which can enter various arterial vessels of the
brain and cause permanent brain damage. Attempts to treat such
occlusions with a balloon angioplasty have been very limited
because of such dangers. In surgical treatments, the carotid artery
has been slit and plaque removed from the slit area. Such surgical
procedures have substantial risk associated with them which can
lead to morbidity and mortality. In other procedures such as in
angioplasty and in the treatment of peripheral arteries and veins,
there is the possibility that the guide wires and catheters used in
such procedures during deployment of the same may cause
dislodgement of debris or emboli which can flow downstream and
cause serious damage if they occlude blood flow in smaller vessels.
There is therefore need for new and improved apparatus and methods
which makes it possible to treat occluded vessels without
endangering the patient.
In general, it is an object of the present invention to provide a
catheter apparatus or assembly and method for treating occluded
vessels which makes it possible to prevent downstream flow of
debris or emboli.
Another object of the invention is to provide an apparatus and
method which makes it possible to reverse the flow of blood in an
occluded vessel during the time that a stenosis is being
crossed.
Another object of the invention is to provide an apparatus and
method of the above character in which a negative pressure is
created within the vessel to reverse the flow of blood in the
vessel.
Another object of the invention is to provide an apparatus and
method of the above character in which it is only necessary to stop
the flow of blood in a vessel of a patient for a very short period
of time.
Another object of the invention is to provide an apparatus and
method in which a working space is provided in the vessel free of
blood for treatment of the stenosis.
Another object of the invention is to provide an apparatus and
method of the above character in which material which is removed
during the treatment of the occlusion or stenosis is removed by
suction.
Another object of the invention is to provide an apparatus and
method of the above character in which blood is shunted around the
working space.
Another object of the invention is to provide an apparatus and
method in which a cutting device is utilized for treatment of the
stenosis or atheroma in the vessel and in which the material
removed from the stenosis or atheroma is aspirated out of the
operating space.
Another object of the invention is to provide an apparatus and
method of the above character in which the amount of material
removed from the stenosis or atheroma can be precisely
controlled.
Another object of the invention is to provide an apparatus and
method of the above character which makes it possible to treat
stenoses or occlusion in the vessel which are normally not
accessible for surgical procedures.
Another object of the invention is to provide an apparatus and
method of the above character which utilizes two spaced apart
balloons to create the working space in the vessel.
Another object of the invention is to provide an apparatus and
method of the above character that can be utilized to create a
working space in a vessel having a bifurcation therein and in which
the working space includes the bifurcation.
Another object of the invention is to provide an apparatus and
method of the above character which utilizes three spaced apart
balloons to create the working space in the vessel having a
bifurcation therein.
Another object of the invention is to provide an apparatus and
method of the above character which includes a control console for
controlling the inflation of the blood flow pump.
Another object of the invention is to provide an apparatus and
method of the above character which is particularly adapted for use
with the carotid vessels.
Additional objects and features of the invention will appear from
the following description in which the preferred embodiments are
set forth in detail in conjunction with the accompanying
drawings.
FIG. 1 is a side elevational view partially in section showing the
catheter apparatus or assembly of the present invention for
treating occluded vessels.
FIG. 2 is a cross-sectional view taken along the line 2--2 of FIG.
1.
FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG.
1.
FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG.
1.
FIG. 5 is a schematic illustration of how the catheter apparatus
shown in FIG. 1 is deployed in a carotid artery.
FIGS. 6A--6E are illustrations showing the various steps utilized
in deployment of the catheter apparatus in performing the method of
the present invention in a vessel where a bifurcation is not
present.
FIG. 7 is a side elevational view partially in section of another
embodiment of a catheter apparatus or assembly incorporating the
present invention for treating occluded vessels using an
atherectomy device.
FIG. 8 is a cross-sectional view taken along the line 8--8 of FIG.
7.
FIG. 9 is a cross-sectional view taken along the line 9--9 of FIG.
7.
FIG. 10 is a side elevational view in section of the distal
extremity of another embodiment of a catheter apparatus
incorporating the present invention and utilized for delivering an
expandable stent to a stenosis.
FIG. 11A is a schematic illustration showing the manner in which
the apparatus of the present invention is utilized in connection
with vessels of a patient in performing the method of the present
invention.
FIG. 11B is an additional partial schematic illustration showing
interconnections in the catheter apparatus shown in FIG. 11A.
FIG. 12 is a plan view of another embodiment of a catheter
apparatus incorporating the present invention.
FIG. 13 is a cross-sectional view taken along the line 13--13 of
FIG. 12.
FIG. 14 is an enlarged isometric view of the control console shown
in FIG. 11 utilized in the present invention.
FIGS. 15A, B, C, D and E are illustrations showing the method of
the present invention being utilized with the apparatus shown in
FIG. 11 in a vessel having a bifurcation therein.
In general, the catheter apparatus of the present invention is for
treatment of a stenosis in a lumen in a blood carrying vessel in
which the stenosis has a length and a width or thickness which at
least partially occludes the lumen in the vessel. The apparatus is
comprised of a first flexible elongate tubular member having
proximal and distal extremities. A first inflatable elastic balloon
is coaxially mounted on the distal extremity of the first tubular
member. The first tubular member has therein a centrally disposed
lumen, a balloon inflation lumen in communication with the interior
of the first inflatable balloon and an aspiration lumen exiting
through the distal extremity. A second flexible elongate tubular
member is provided which extends through the centrally disposed
lumen of the first tubular member and has proximal and distal
extremities. A second inflatable balloon is coaxially mounted on
the distal extremity of the second tubular member. The second
tubular member has a balloon inflation lumen therein in
communication with the interior of the second balloon. The second
tubular member is also provided with a guide wire and/or fluid flow
lumen for or blood. Means is carried by the proximal extremity of
the first and second tubular members permitting advancement of the
first balloon into position proximal of the occlusion in the vessel
and for inflating the same and for creating suction on the
aspiration lumen to aspirate the space in the vessel distal of the
first balloon and thereafter permitting placement of the second
balloon distal of the occlusion and inflation of the second balloon
to create a working space between the first and second balloons and
for shunting arterial blood from the arterial blood flow lumen into
the vessel distal of the second balloon. A third flexible elongate
tubular member is provided which extends through the centrally
disposed lumen of the first tubular member and has a lumen therein
through which the second tubular member extends. Means is carried
by the distal extremity of the third tubular member for performing
a medical procedure in the working space created between the first
and second balloons which brackets the stenosis.
More particularly as shown in FIGS. 1-4 of the drawings, the
catheter apparatus 11 of the present invention which is for use in
the treatment of a stenosis 12 in a lumen 13 in a blood-carrying
vessel 14 in which the stenosis 12 has a length and a width or
thickness which at least partially occludes the lumen 13. The
apparatus consists of a first elongate flexible tubular member 16
formed of a suitable plastic material which is provided with
proximal and distal extremities 17 and 18. A first balloon 19 is
mounted on the distal extremity 18 and preferably is a compliant
balloon formed of a suitable elastic material such as a latex or a
very low radiation polyethylene so that it can be inflated to the
size of the vessel 12 in which it is to be disposed. Thus, the
balloon 19 should be capable of expanding to various diameters
depending on the size of the vessel. The first balloon 19 can be
formed as a separate balloon separate from the elongate tubular
member 16 as shown and adhered thereto by suitable means such as an
adhesive (not shown), or it can be formed integral with the tubular
member 16 in a manner well known to those skilled in the art.
The tubular member 16 is provided with a large centrally disposed
or main lumen 21 extending from the proximal extremity 17 to the
distal extremity 18. It is also provided with a balloon inflation
lumen 22 which has a distal extremity in communication with the
interior of the first balloon 16 through a port 23. The proximal
extremity of the balloon inflation lumen 22 is in communication
with a balloon inflation fitting 24 mounted on the proximal
extremity 13 of the tubular member 12. The fitting 24 can be of a
conventional type as for example a Luer-type fitting which is
adapted to be connected to a balloon inflation device (not shown)
for inflating and deflating the first balloon 16.
The first tubular member 16 is also provided with an aspiration
lumen 26 which exits through the distal extremity 13 and the
proximal extremity 14 of the tubular member 12. A Luer-type fitting
27 is mounted on the proximal extremity 14 and is in communication
with the aspiration lumen 26. The fitting 27 is adapted to be
connected to a suitable aspiration or suction source (not shown) of
a conventional type for aspiration purposes as hereinafter
described.
The catheter assembly or apparatus 11 also consists of a second
elongate flexible tubular member 31 having proximal and distal
extremities 32 and 33. A second inflatable balloon 36 of the same
type as the first inflatable balloon is coaxially mounted on the
distal extremity 33 in a conventional manner. The tubular member 31
is provided with a large generally centrally disposed arterial
blood flow lumen 37 which opens through the distal extremity 33 and
is in communication with a Luer-type fitting 38 which as
hereinafter described is adapted to be connected to a supply of
arterial blood from the patient which for example can be taken from
another femoral artery of the patient by the use of a blood
pump.
The second tubular member 31 is also provided with a balloon
inflation lumen 39 which is in communication with the interior of
the second inflatable balloon 36 through a port 41. The proximal
extremity of the lumen 39 is in communication with the Luer-type
fitting 42 mounted on the proximal extremity 32 of the second
tubular member 31 and as with the balloon inflation fitting 24 is
adapted to be connected to a balloon inflation deflation device
(not shown) of a conventional type. The second tubular member 31 is
also provided with a lumen 43 which also can be used as a guide
wire and/or for introducing a saline solution extending from the
proximal extremity to the distal extremity. The lumen 43 is sized
so that it is adapted to receive a conventional guide wire 46 as
for example a 0.014" or 0.018" guide wire and extends from the
proximal extremity to the distal extremity so that the guide wire
46 can extend beyond the distal extremity of the second tubular
member 31. A fitting 47 is provided on the proximal extremity 32 in
communication with the lumen 43 for introducing the saline
solution.
As shown in FIG. 1, the second tubular member 31 is disposed within
the central lumen 21 of the first tubular member 12 and is slidably
and coaxially mounted therein for displacement of the second
balloon 36 with respect to the first balloon 16 as hereinafter
described.
The catheter assembly or apparatus 11 also consists of a third
elongate flexible tubular member 51 having proximal and distal
extremities 52 and 53. It is provided with a centrally disposed
lumen 56 extending from the proximal extremity 52 to the distal
extremity 53 and through which the second tubular member 31 is
coaxially and slidably mounted.
Means 57 is provided on the distal extremity 53 of the third
tubular member 51 for performing a medical procedure. In the
embodiment of the invention shown in FIG. 1, this means 57 consists
of a third balloon 58 which can be non-compliant coaxially mounted
on the distal extremity of the third tubular member 51. The third
balloon 58 can be attached in the same manner as the first and
second balloons 19 and 36 hereinbefore described. The third tubular
member 51 is provided with a balloon inflation lumen 59 which has
its distal extremity in communication with the interior of the
balloon 58 through a port 61. The proximal extremity of the balloon
inflation 59 is in communication with a Luer- type fitting 62
provided on the proximal extremity 52 and adapted to be connected
to a conventional inflation deflation device (not shown) for
inflating and deflating the third balloon 58.
The operation and use of the catheter assembly or apparatus 11 in
the method of the present invention for treating occluded vessels
may now be briefly described in connection with an occlusion formed
by a stenosis in a vessel not having a bifurcation therein as for
example in saphenous graft or in one of the right and left carotid
arteries, also called internal and external carotid arteries, of a
patient in connection with the illustrations shown in FIGS. 5 and
6A-6E. A guiding catheter 63 (FIG. 5) of a conventional type is
inserted into an incision into a femoral artery of a patient and is
advanced through that artery into the aorta 64 of the heart 65 of
the patient and into the ostium 66 of the selected carotid artery
or vessel as for example the left carotid 67. As is well known to
those skilled in the art of anatomy, the left carotid 67 is
provided with a bifurcation 68 which leads to internal and external
carotids 71 and 72. A right carotid 73 is provided which also
extends into a bifurcation (not shown) and internal and external
carotids (not shown).
After the guiding catheter has been appropriately positioned, the
guide wire 46 is introduced separately into the guiding catheter or
along with the catheter assembly 11. The distal extremity of the
catheter apparatus or assembly 11 with all of the first, second and
third balloons 19, 36 and 58 completely deflated, is introduced
into the guiding catheter 63 along with or over the guide wire 46
and is advanced through the guiding catheter 63 into the ostium 66
of the carotid artery or vessel 67 and into the lumen or passageway
68 of the vessel as shown in FIGS. 5 and 6B.
The distal extremity of the catheter assembly 11 is advanced until
it is just proximal of a stenosis 76 in the carotid artery 67 to be
treated. The balloon 19 is then inflated by introducing a suitable
inflation medium such as a radiopaque liquid into the fitting 24 to
cause it to pass through the balloon inflation lumen 22 through the
port 23 and into the interior of the first balloon 19 to inflate
the same as shown in FIG. 6A. The balloon 19 is progressively
inflated until it engages the side wall of the vessel 67 to occlude
the vessel 67. At the time that this is occurring, a negative
pressure or suction is applied to the aspiration fitting 27 to
supply a negative pressure through the balloon inflation lumen 22
to suck or aspirate blood in the vessel 67 distal of the first
balloon 16 into the lumen and out the aspiration port 62 to thereby
reverse the flow of blood through the stenosis as shown by the
arrows 71 in FIG. 6B.
While a reverse flow of blood is occurring in the vessel 67, the
guide wire 46 is advanced through the stenosis 76 as shown in FIG.
6C. In the event that any pieces or particles of plaque are knocked
off of the occlusion formed by the stenosis 76 by movement of the
guide wire 46 through the same, such pieces of plaque or emboli
will be drawn out with the reverse flow of blood into the
aspiration lumen 26 and out of the aspiration fitting 27. During
the time that the guide wire 46 is being advanced through the
stenosis 67 it may be desirable at the same time to introduce a
saline solution through the guide wire lumen 43 of the second
elongate flexible tubular member 31 to exit through the distal
extremity of the second elongate flexible tubular member 31 into
the space immediately proximal of the stenosis 67. This introduced
saline solution aids the flow of particulate or other particles
dislodged from the stenosis 76 during advancement of the guide wire
46 through the same and carries them back with the mixed saline
blood solution through the aspiration lumen 26 in a manner
hereinbefore described.
With the guide wire 46 remaining in position, the second elongate
flexible tubular member 31 with the second balloon 36 thereon in a
deflated condition is advanced over the guide wire 46 through the
stenosis 76 until -the second balloon 36 is distal of the stenosis
76 as shown in FIG. 6D after which the second balloon 36 is
inflated by introducing an inflation medium as for example a
radiopaque liquid through the inflation fitting 42 into the lumen
39 through the port 41 to the interior of the second balloon 36 to
inflate the second balloon 36 until it engages the sidewall of the
vessel 67.
Prior to, during or after inflation of the second balloon 36, the
guide wire 46 can be removed. However, it is preferable to remove
the guide wire 46 as soon as the second balloon 36 has been
advanced so that it is beyond the stenosis 76. At this time, and
certainly prior to complete inflation of the second balloon 36,
blood is shunted across the stenosis 76 and into the lumen 68
distal of the second balloon 36 by introducing blood through the
fitting 38 and into the centrally disposed blood flow lumen 37 in
the second tubular member 31 so that it exits out the central lumen
37 distal of the second balloon 36. The blood which is supplied to
the fitting 37 can be taken from another femoral artery of the
patient and pumped into the fitting 38. In addition, if desired,
the blood which is aspirated in the space distal of the first
balloon 16 can be appropriately filtered and also supplied to the
fitting 38. By shunting blood past the stenosis 69 in this manner
it can be seen that blood is being continuously supplied to the
carotid artery of the patient during the time that the second
balloon 36 is inflated and occludes the lumen 68 in the vessel
67.
As soon as the second balloon 36 has been inflated, it can be seen
that there is provided a working space 78 (FIG. 6D) between the
first and second balloons 19 and 36 so that medical procedures can
be undertaken to remove or reduce the stenosis 76 in the space
between the first and second balloons 19 and 36.
Assuming that it is desired to compress the plaque or material
forming the stenosis 76 to provide a larger lumen,-opening or
passageway through the stenosis 76, the third tubular member 51 can
be advanced by grasping the proximal extremity 52 to cause the
distal extremity with the third balloon 58 thereon to be advanced
into the space 78. As soon as the balloon 58 has been properly
positioned within the stenosis 76, the balloon 58 also can be
inflated with a suitable inflation medium as for example a
radiopaque liquid. The balloon 58 can be inflated to the desired
pressure to cause compression of the plaque of the occlusion
against the sidewall of the vessel 67 by the application of
appropriate pressure. As in conventional angioplasty procedures,
the third balloon 58 can be formed of a non-elastic relatively
non-compliant material so that high pressures as for example 10-15
atmospheres can be used within the balloon to apply compressive
forces to the vessel without danger of rupturing the vessel. It
should be appreciated that the non-elastic capabilities can also be
achieved by a composite elastic material.
Since the blood flow has been restored to the vessel 67 by the
shunt hereinbefore described, the compression of the occlusion
forming the stenosis 76 can be carried out for an extended period
of time, as for example after a few minutes, if desired to help
ensure that a large lumen or passageway is formed through the
stenosis 76 as shown in FIG. 6E. If it is believed that the
occlusion forming the stenosis 69 has been sufficiently compressed,
the third balloon 58 can be deflated. In the event an inelastic
balloon is utilized for the third balloon 58, and it is desired to
utilize a larger third balloon, this can be accomplished by
removing the third tubular member 51 with the deflated balloon 58
thereon and introducing a third tubular member 51 having a larger
size balloon thereon over the second tubular member 31 and
advancing it into the stenosis 69 and inflating the larger size
balloon to create a still larger passage through the stenosis
76.
After the appropriate dilation the stenosis 76 has been
accomplished the third balloon can be removed from the stenosis
while aspiration of the space 78 is still ongoing so that any
plaque coming off the occlusion forming the stenosis 67 can be
aspirated out of the vessel. After the third balloon 58 has been
removed from the stenosis, the second balloon 36 and the first
balloon 16 can be deflated to permit normal blood flow through the
vessel 61 after which the arterial blood flow supply to the fitting
38 can be terminated. The entire catheter assembly 11 can then be
removed from the guiding catheter 63 after which the guiding
catheter 63 can be removed and a suture applied to the incision
created to obtain access to the femoral artery.
In place of the third balloon 58 for causing compression of the
occlusion forming the stenosis 67 to create a larger passageway
therethrough, an atherectomy device 81 can be utilized for
operating in the working space 78 to remove the plaque of the
occlusion forming the stenosis. This can be accomplished with a
catheter assembly or apparatus 81 which in many respects is similar
to the apparatus 11 shown in FIG. 1 and consists of a first tubular
member 16 with a first balloon 19 and a second tubular 31 with a
second balloon 36 thereon. In place of the third flexible elongate
tubular member 51 there is provided a third flexible elongate
tubular member 86 which is provided with proximal and distal
extremities 87 and 88. The flexible elongate tubular member 86 is
slidably and rotatably mounted in the central lumen 21 of the
flexible elongate member 16 and is provided with a central or main
lumen 89 through which the second flexible elongate tubular member
31 extends. It is also provided with a lumen 91 extending from the
proximal extremity to the distal extremity through which a saline
solution can be introduced for saline irrigation as hereinafter
described. It is also provided with another lumen 92 which is
adapted to receive a plurality of electrical conductors 93 for
performing electrical functions as hereinafter described. The lumen
92 is connected to a conventional Luer-type fitting 96 serving as a
fluid irrigation fitting mounted on the proximal extremity first
tubular member 12 and is in communication with an annular recess 97
which is in communication with the lumen 91 provided in the tubular
member 86 for supplying a saline irrigation liquid through the
flexible elongate tubular member 86 and into the working space 78
provided between the first and second balloons 16 and 36. In order
to aid aspiration of the saline irrigation liquid from the working
space 78, the outer surface of the flexible elongate tubular member
86 is provided with a helical groove 98 therein which has one end
which opens into the working space 78 and which has the other end
in communication with the aspiration fitting 27.
Means is provided for rotating the second tubular member 86 and
consists of suitable means such as a spur gear 101 mounted on the
proximal extremity 87 of the tubular member 86. The spur gear 101
is driven in a suitable manner as for example by another smaller
spur gear 102 which is of greater width than spur gear 101 so as to
provide a splined gear connection between the gears 101 and 102.
This accommodates the desired longitudinal movement for the tubular
member 86 so that the distal extremity 88 of the tubular member 86
can be advanced and retracted in the working space 78 as
hereinbefore described. An electrical drive motor 103 is provided
for driving the gear 102.
Atherectomy means 106 is provided on the distal extremity 88 of the
flexible elongate tubular member 86. As shown in FIGS. 7 and 9, the
atherectomy means 106 consists of a flexible elongate member 107
formed of a suitable material such as stainless steel or preferably
a superelastic Nitinol. The flexible elongate member 107 is wound
into a helix as shown in FIG. 9 onto the distal extremity of the
tubular member 86. The flexible elongate member 107 can be formed
of a ribbon having a thickness of 0.003" and a width of 0.060". One
end of the flexible elongate member 107 can be secured to the
tubular member 86, as for example by inserting the same into a slit
108 and additionally by the use of adhesive (not shown). The
flexible elongate member 107 is wrapped into a helix in a direction
opposite to the direction of normal rotation of the tubular member
86 and can be provided with a special tip 109 on its free end with
the tip having an arcuate surface 111 that is inclined rearwardly
to terminate at a cutting edge 112 (see FIG. 9) which is adapted to
engage the plaque or the stenosis 76.
When the distal extremity 88 of the flexible elongate tubular
member 86 has been introduced into the working space 78, the end or
tip 109 of the flexible elongate member 107 of the atherectomy
means 106 is free. A saline solution is introduced into the fitting
57. Thereafter the motor 103 can be energized to cause rotation of
the tubular member 86 and to thereby cause rotation of the
helically wound flexible elongate member 107 to cause its free end
or tip 109 to be moved outwardly radially under centrifugal force
to bring the cutting edge 112 into engagement with the plaque 69 in
the stenosis 76 to cause progressive removal of the plaque forming
the stenosis 76 to enlarge the passageway extending through the
stenosis. Because of the rounded configuration of the tip 109, the
tip 109 will not dig into the vessel wall but will only remove
plaque which is engaged by the cutting edge 112. As the plaque is
being removed, the saline solution introduced through the fitting
96 into the space 78 picks up the plaque particles or emboli as
they are being removed. The saline solution with the plaque or
emboli therein is removed through the spiral groove 98 and through
the aspiration port 27. The flexible elongate tubular member 86 can
be moved back and forth so that the cutting tip 109 engages the
length of the stenosis 76 so that substantially all of the stenosis
76 can be removed.
Means is provided to sense when sufficient plaque has been removed
from the stenosis 76 and to ensure that cutting edge 112 does not
cut into the vessel wall. An ultrasonic sensor 116 is mounted in
the distal extremity of the tubular member 86 and is connected by
conductors 93 extending through the lumen 92 and connected to a
cable 118 which is connected to an ultrasonic power supply 119 and
a video monitor 121. By using the Doppler effect, ultrasonic energy
can be utilized in connection with the transducer 116 to ascertain
the depth of cut being made by the flexible elongate member 107 as
it is being rotated.
As soon as a desired amount of plaque has been removed from the
stenosis 69 to provide the desired passage through the stenosis,
rotation of the tubular member 86 is terminated after which the
tubular member 86 can be withdrawn followed by deflation of the
second balloon 36 and withdrawing it, deflation of the first
balloon 16 and withdrawing it from the vessel 67. Thereafter, the
guiding catheter 63 can be removed and the incision closed as
hereinbefore described.
In order to ensure that restenosis will not take place, it may be
desirable to place a cylindrical stent 126 in the stenosis 76. Such
a stent 126 can be a self-expanding stent formed of a suitable
material such as a superelastic Nitinol and movable between
unexpanded and expanded conditions. Such a stent 126 can be placed
by a suitable catheter apparatus 131 of the type shown in FIG. 10.
The stent 126 which is cylindrical in form is pushed over the
proximal extremity of the second elongate flexible tubular member
31 into the main or central lumen 21 so that it is retained in the
unexpanded position. It is then pushed forwardly toward the distal
extremity of the first flexible elongate tubular member 16 by means
of a flexible elongate tubular member 136 having proximal and
distal extremities 137 and 138 and having a flow passage 139
extending from the proximal extremity 137 to the distal extremity
138. The proximal extremity 137 is provided with a knurled collar
141 which is adapted to be engaged by the hand to facilitate
pushing of the flexible elongate tubular member 136 so that its
distal extremity is in engagement with the stent 126. Thus, when
desired the stent 126 may be discharged or dislodged from the
distal extremity of the second tubular member 31 and pushed into
the working space 71 created between the first balloon 19 and the
second balloon 36.
After the stent 126 has been discharged out of the end of the first
flexible elongate tubular member 16, the stent 126 will self expand
toward its expanded condition until it is in engagement with the
wall of the vessel in the vicinity of the occlusion forming the
stenosis 76 to frictionally retain the stent in engagement with the
vessel wall. As soon as the stent 126 is in engagement with the
vessel wall, the second balloon 36 can be deflated as can the first
balloon 19. The first deflated balloon 36 can then be withdrawn
through the interior of the cylindrical stent 126. This can be
followed by deflation of the first balloon 19 and the removal of
the flexible elongate tubular member 16 with its first balloon 19
and the flexible tubular member 31 with its second balloon 36,
along with the flexible elongate member 136 until the entire
catheter assembly or apparatus 131 has been removed from the
guiding catheter 63. Thereafter the guiding catheter 63 can be
removed and the incision sutured as hereinbefore described.
In FIG. 11, there is shown another embodiment of an apparatus 151
incorporating the present invention which is particularly adapted
for use treating a stenosis at or near a bifurcation appearing in
an arterial vessel. The apparatus 151 is shown being used on a
human being 152 showing the principal arteries and pulmonary veins
of the human body. Thus there as shown, the abdominal aorta 153
branches into the common iliac 154 which branches into the external
iliac 156 and the internal iliac 157. The external iliac branches
into the deep femoral artery 158 and into the femoral artery 159.
The abdominal aorta 153 extending in the opposite direction passes
through the aortic arch 161 of the heart 162. The aortic arch 161
is connected to the common carotid 166 which extends into a
bifurcation branching into the external carotid 167 the internal
carotid 168. Similar bifurcations appear in the basilar artery
which is an artery which is particularly inaccessible for surgical
treatment.
As hereinafter explained, the apparatus 151 shown in FIGS. 11, 12
and 13 consists of a proximal occlusion balloon catheter 176 which
can be considered to be a first catheter. The catheter 176 is
formed of a flexible elongate tubular member 177 having proximal
and distal extremities 178 and 179. The tubular member 177 is
formed of a suitable material such as plastic and can have a
suitable size ranging from 5 to 14 French and preferably 9 to 10
French. A balloon 181 is provided on the distal extremity 179 and
is formed of a suitable elastic material. It is generally
cylindrical in form and has its proximal and distal extremities
secured to the tubular member 177 by suitable means such as an
adhesive (not shown). The tubular member 177 is provided with a
plurality of lumens therein. One lumen 182 serves as a balloon
inflation lumen and extends from the proximal extremity 178. It can
have a suitable size such as 0.024" and has port 183 in
communication with the interior of the balloon 181. A manifold 186
formed of a suitable material such as plastic is mounted on the
proximal extremity 178. A tubular member 187 is mounted in the
manifold 186 and is in communication with the inflation lumen
182.
The tubular member 177 is also provided with a large lumen 191
having a suitable size as for example 0.045" which is adapted to
slidably receive therein a therapeutic balloon catheter 192 and a
perfusion balloon catheter 193. It is also provided with another
lumen 196 having a suitable size as for example 0.026" which is
adapted to receive a balloon-on-a-wire catheter 197. It is also
provided with an aspiration lumen 201 having a suitable suize as
for example 0.025" and an irrigation lumen 202 having a suitable
size as for example 0.015". There is also provided another lumen
203 which can be used for other purposes.
The therapeutic balloon catheter 192 and the perfusion balloon
catheter 193 are constructed in a manner similar to the balloon
catheters hereinbefore described. Thus the perfusion balloon
catheter 193 is provided with a flexible elongate tubular member
206 having proximal and distal extremities 207 and 208. A balloon
209 formed of an elastic material is secured to the distal
extremity 208 by suitable means such as an adhesive (not shown) and
is adapted to be inflated through a port 210 in communication with
a balloon inflation lumen 211. The tubular member 206 is also
provided with a blood perfusion lumen 212 which is centrally
disposed therein. The proximal extremity 207 of the tubular member
206 is connected to a Y adapter or fitting 213 of which the central
arm 214 is in communication with the blood perfusion lumen 212 and
is provided with a Luer-type fitting 216. The side arm 217 of the
fitting 213 is in communication with the balloon inflation lumen
211 and is provided with a Luer-type fitting 218 adapted to be
connected to a source of pressure as hereinafter described.
The therapeutic balloon catheter 192 consists of a tubular member
221 having a proximal and distal extremities 222 and 223. A balloon
224 formed of a non-elastic material is secured to the distal
extremity 223 by suitable means such as an adhesive. A port (not
shown) is in communication with the interior of the balloon 224 and
is in communication with a balloon inflation lumen 226. A Luer-type
fitting 227 is mounted on the proximal extremity 222 and is in
communication with the balloon inflation lumen 226. Another fitting
228 is mounted on the proximal extremity 222 and is in
communication with a large centrally disposed lumen 229 which can
receive the perfusion balloon catheter 193 for slidable movement as
hereinafter described.
The balloon-on-a-wire catheter 197 is slidably mounted in the lumen
196 and consists of a guide wire 231 of a conventional construction
having a suitable diameter as for example 0.018" and having a
proximal and distal extremities 232 and 233. A balloon 234 formed
of a non-elastic material is mounted on the distal extremity 233
and is secured thereto by suitable means such as an adhesive (not
shown). The proximal extremity of the balloon 234 is secured to the
distal extremity of a tubular member 236 formed of a suitable
material such as plastic and which is coaxially disposed on the
guide wire 231. The tubular member 236 extends the length of the
guide wire to the proximal extremity and is connected to a
Luer-type wye fitting 237 and is in communication with an annular
lumen 238 disposed between the tubular member 236 and the exterior
surface of the guide wire 231. The lumen 238 is in communication
with the interior of the balloon 234 for inflating and deflating
the balloon 234. The balloon-on-a-wire catheter 197 is adapted to
be introduced through a fitting 241 carried by a tube 242 mounted
in the manifold 186 and in communication with the lumen 196 in the
multi-lumen elongate tubular member 177.
A tube 246 is mounted in the manifold 186 and is in communication
with the large lumen 191 and is provided with a fitting 247 which
is adapted to receive the perfusion balloon catheter 193 and the
therapeutic balloon catheter 192 as hereinafter described. Another
tube 251 is provided in the manifold 186 and is in communication
with the aspiration lumen 201. It is provided with the fitting 252.
Another tube fit 253 is mounted in the manifold 186 and is in
communication with the irrigation lumen 202 and is provided with a
fitting 254.
The various fittings for the catheter as hereinbefore described are
adapted to be connected into a control console. The control console
consists of a rectangular case 272 which is provided with a front
panel 273.
A plurality of balloon inflation deflation devices 276 of a
conventional type typically called endoflaters are mounted within
the case 272 and have control handles 277 extending through
vertically disposed slots 278 provided in the front panel. These
endoflaters 276 are labeled as shown in FIG. 11 and are connected
by tubing (not shown) through pressure gauges 281 mounted in the
front panel 273 and are provided with needle indicators 282 to
indicate the pressure being applied by the endoflater to the
tubing. The tubing is connected in such a manner so that the
endoflater 276 and the associated pressure gauge 281 are connected
to a tube 286 which is provided with a mating fitting 287 adapted
to mate with a fitting 188 so that it is in communication with the
inflation lumen 182 of the proximal occlusion balloon catheter 176.
In a similar manner, the tubing 288 is provided with a fitting 289
which mates with a fitting 218 of the balloon inflation lumen 211
of the perfusion balloon catheter 193 for inflating balloon 209.
Similarly, tube 291 with its mating fitting 92 is adapted to mate
with the fitting 237 for inflating the balloon 234. Similarly, the
tube 293 with its fitting 294 mates with the fitting 227 in
communication with the balloon inflation lumen 226 for inflating
the balloon 224 of the therapeutic catheter 192. Another tube 296
which is provided with its fitting 297 mates with the fitting 252
that is in communication with the aspiration lumen 201. The tube
296 is in communication with the inlet of a blood pump 301 of a
suitable type as for example a roller pump well known to those
skilled in the art which is mounted within the case 272 and which
is connected to a source of electrical power through electrical
plug 302 connected into the case 272. The roller pump 301 is
provided with an on/off switch 303 mounted on the front panel 273.
After it passes through the pump 301, blood is supplied to a blood
filter 306 of a conventional type and then is supplied through a
tube 311 having a fitting 312 adapted to mate with the fitting 216
of the perfusion balloon catheter which is in communication with
the perfusion lumen 212.
A three-way valve 316 is associated with each of the endoflaters
276 and has a control knob 317 extending through the front panel
273 and is adaptable to be moved between three positions with a
center off position and an aspiration position in a
counter-clockwise direction and a pressurized position in a
clockwise position as viewed in FIG. 14.
Operation and use of the apparatus 151 may now be briefly described
as follows. Let it be assumed that it is desired to treat a
stenosis occurring in a bifurcation in a carotid artery as depicted
by the illustrations shown in FIGS. 15A through 15D. As shown in
the illustration in FIG. 15A, let it be assumed that a stenosis is
present adjacent the bifurcation 167 and in the internal carotid
169 and that it is desired to treat this stenosis in accordance
with the apparatus 151 of the present invention in performing the
method of the present invention. The proximal occlusion balloon
catheter 176 is loaded with the therapeutic balloon catheter 192
slidably mounted over the perfusion balloon cathete 193 and both
are slidably mounted in the main lumen 191. The balloon-on-a-wire
catheter 197 is slidably mounted in the lumen. While the patient is
being prepared for the procedure, all of the lumens in the
catheters of the apparatus are flushed with saline to remove all
air from the lumens. They are then connected to the control console
271 in the manner hereinbefore described and as shown in FIG. 11.
An incision 326 (see FIG. 11) is made in the femoral artery in the
left leg of the patient and a guiding catheter (not shown) similar
to the type utilized in angioplasty is introduced through the
femoral artery 159. This guiding catheter is advanced until it is
near the aorta arch 161. Thereafter, the first or proximal
occlusion balloon catheter 176 has its distal extremity 179
introduced into the guiding catheter and advanced in the guiding
catheter. It is advanced so that its distal extremity 179 enters
the common carotid and is near the bifurcation 167. The balloon 181
is inflated by operating the control handle 277 associated with the
proximal occlusion balloon 181 as shown in FIG. 15A to create the
desired pressure within and to inflate the elastic balloon 181 so
that it occludes the common carotid just proximal of the stenosis
324. As soon as this occurs, the roller pump 301 is turned on by
operating the on/off switch 303 to create a negative pressure on
the distal side of the balloon 181 to cause blood to flow in a
reverse direction as shown by arrows 326 to thereby change the
directional flow of blood from the internal and external carotids
away from the brain rather than to the brain. The blood travels
into the aspiration lumen 201 as indicated by the arrows 326 and
into the tube 251 through fittings 252 and 297 and tube 296 to the
roller pump 303. The blood after passing through the roller pump
303 passes through a blood filter 306 and then passes into the tube
311 and the fitting 312 and connected to the fitting 289 of the
perfusion catheter 193. Alternatively, the fitting 312 can be
connected to another fitting 331 mounted on a tube 332 introduced
into the venous side of the circulatory system of the patient's
body, as for example into the vein in the right leg of the patient
152 as shown in FIG. 11. Any debris or emboli in the aspirated
blood being pumped will be filtered out by the blood filter
306.
As soon as or during the time this retrograde circulation of blood
is established through the roller pump 301, the perfusion balloon
catheter 193 extending proximally from the fitting 247 is advanced
into the internal carotid 169 past the stenosis 321 at the
bifurcation 167. If necessary, a guide wire can be utilized which
can be introduced through the perfusion lumen 212 to aide in
advancing the perfusion balloon catheter 193 into the internal
carotid 169. Any emboli or debris dislodged from the stenosis 321
by crossing the same either by the guide wire or by the distal
extremity of the catheter 193 will be picked up by the retrograde
flow of blood which is being aspirated through the proximal
occlusion balloon catheter 176 to thereby prevent any emboli or
debris from entering the brain of the patient. The elastic
perfusion balloon 209 is then inflated as shown in FIG. 15B using
the appropriate endoflater to inflate the balloon to the desired
pressure while watching the associated pressure gauge. As soon as
occlusion occurs, perfusion of blood can be started as hereinafter
described.
Prior to or after the balloon 209 of perfusion catheter 193 has
been inflated, the balloon-on-a-wire catheter 197 extending
proximally of the fitting 241 is advanced into the external carotid
169 as shown in FIG. 15C. The balloon 234 is then expanded by use
of the appropriate endoflater to supply an inflating medium through
the fitting 237 to occlude the external carotid 169. As soon as
occlusion has been accomplished in both the external and internal
carotids, retrograde flow of blood is terminated by shutting off
the roller pump 301. It should be appreciated that if desired,
automatic controls can be provided whereby when a certain pressure
is reached in each of the balloons 209 and 234 the roller pump
would automatically be shut off to stop retrograde flow. By this
procedure, it can be seen that the lesion of stenosis 321 has been
bracketed by the balloons 181, 209 and 234. Prior to that
occurring, retrograde flow of blood is established to prevent any
emboli or debris from moving towards the brain.
As soon as retrograde flow of blood has been terminated, perfusion
of blood is started. This can be accomplished by connecting a
cannula (not shown) to the fitting 216 of the perfusion catheter
206 and to obtain a supply of blood from the femoral artery in the
other leg of the patient. Alternatively, an outside blood supply
can be used. Thus fresh blood will be supplied from the femoral
artery of the patient directly into the perfusion balloon so that
it is discharged distally of the perfusion balloon 209 as shown by
the arrows 327 to continue to supply blood to the carotid artery.
It has been found that it is unnecessary to a supply perfusion of
blood to the external carotid artery because there is sufficient
auxiliary circulation in that carotid artery during the time the
procedure is taking place.
In the event there is inadequate pressure on the arterial blood
being profused to overcome the resistance in the lumen 169, the
roller pump 301 can be utilized by merely operating the same in a
reverse direction and connecting it between the cannula and the
perfusion catheter.
After the lesion or stenosis 321 has been bracketed as hereinbefore
described and a working space 336 formed adjacent the stenosis or
lesion 321, a therapeutic procedure can be employed. By way of
example this can consist of advancing the therapeutic balloon
catheter 192 over and axially of the perfusion catheter 193 to
bring its balloon 224 into registration with the stenosis 321 as
shown in FIG. 15D. Thereafter, the balloon 224 can be inflated by
use of the appropriate endoflater as hereinbefore described to
cause the inelastic balloon to be pressurized to a pressure of 10
to 15 atmospheres to compress the stenosis 321. Prior to or during
this procedure it may be desirable to introduce a saline or heparin
solution or a radiopaque contrast liquid into the working space
336. This can be accomplished by introducing this liquid through
the injection lumen 202. If desired, this can be accomplished prior
to terminating the aspiration procedure hereinbefore described.
Also it should be appreciated that if desired a small endoscope can
be inserted through one of the lumens to view the area within the
working space. Alternatively, if desired an ultrasonic probe can be
utilized to view the area in which the lesion is disposed.
As hereinbefore described with a previous embodiment, in place of
the therapeutic balloon catheter, other types of catheters can be
utilized as for example one incorporating an atherectomy device of
the type hereinbefore described to facilitate removal of the
stenosis. It is readily apparent that during these procedures if it
is necessary to supply a saline solution or a heparinized solution
into the working space that the working space can also be continued
to be aspirated to remove any debris or emboli which occur during
the procedure.
Let it be assumed that the desired therapeutic actions have been
undertaken and that the stenosis 321 has been reduced and
substantially eliminated so that there is adequate flow through the
internal carotid. If it can be seen that there also is a stenosis
in the external carotid, the balloon-on-a-wire catheter 197 and the
perfusion catheter 193 can be withdrawn and moved so that they
enter the opposite carotid to permit therapeutic treatment of a
stenosis occurring in the other carotid.
When all the desired therapeutic procedures have been accomplished,
the supply of saline or contrast solution can be terminated and the
therapeutic balloon 224 deflated. The balloon 234 of the
balloon-on-a-wire catheter can be deflated as well as the perfusion
balloon 209. Perfusion of blood through the perfusion catheter can
be terminated. The perfusion balloon catheter 193 and the
balloon-on-a-wire catheter 197 can be retracted into the main
multi-lumen tubular member 177 of the proximal occlusion balloon
catheter after which-the perfusion balloon catheter can be
withdrawn carrying with it the other catheters disposed therein.
Thereafter, the guiding catheter can be removed and a suture
applied to the incision made to gain access to the femoral
artery.
It is readily apparent that similar procedures can be carried out
with respect to other vessels in the body, such as saphenous vein
grafts in the heart, and particularly with respect to vessels in
the brain where it is difficult if not impossible to employ
surgical procedures as for example with respect to the basilar
arteries in which bifurcations appear.
As also herein before explained, the catheter apparatus of the
present invention can be utilized for deploying stents. Where that
is desirable the apparatus of the present invention, perfusion can
be accomplished during employment of the stent.
From the foregoing it can be seen that an apparatus and method has
been provided for treating occluded vessels and particularly for
treating carotid arteries. The apparatus and method of the present
invention is particularly advantageous for the carotid arteries
because it permits access to portions of the carotid arteries which
are not accessible by surgery. The catheter apparatus assembly and
method of the present invention is also particularly useful for
treating other occluded vessels but particularly the carotid
arteries because it makes possible the removal of plaque without
endangering the patient. An operating or working space is provided
while shunting blood around the working space so that there is
continued blood flow in the vessel to support the functions which
are normally supported by the vessel. As also pointed out above,
the apparatus and method of the present invention are particularly
useful in connection with vessels having bifurcations therein and
in which the stenosis occurs at or near the bifurcation. From the
foregoing it can be seen with the apparatus and method of the
present invention, retrograde flow of blood is accomplished during
deployment of the device to prevent undesired travel of emboli.
Occlusion of the vessels is provided to obtain a working space by
bracketing the working space with balloons while at the same time
maintaining perfusion of blood making it possible to utilize a
substantial period of time for undertaking therapeutic procedures
with respect to the bracketed stenosis.
* * * * *